Abstract: An energy storage system comprises a plurality of electrochemical cells. The electrochemical cells include a pair of electrodes including an anode and a cathode. An electrolyte in communication with the pair of electrodes. A flow shaping baffle is situated between the pair of electrodes. The flow shaping baffle includes a plurality of channels extending from a first end proximate the cathode to a second end proximate the anode along an axis substantially perpendicular to the electrodes. The first end has a first diameter and the second end has a second diameter. The first diameter is greater than the second diameter. The disclosed energy storage system does not require expensive pumps or ion exchange membranes and can operate efficiently over a long service life.